Previous electronic ballast designs have commonly included two switches in order to convert a dc signal into a high-frequency ac signal used to start and operate a discharge lamp. Existing ballast designs have also generally been driven by an integrated circuit, increasing the cost and complexity of the circuit design. Other manners of starting discharge lamps include the use of resistive ballasts having glow bottle starters.
It has therefore been deemed desirable to provide an improved electronic ballast, designed as a class E inverter, which is self-starting, self-oscillating and where the duty ratio is adjustable. It would also be beneficial to have such a ballast constructed with minimal components at a low cost.